It's been five years since microbiologist Henry Heine and other scientists worked in a laboratory in an office building in Albany, New York, developing antibiotics to treat the deadly infectious disease anthrax and doing tuberculosis research on mice.

Security was tight, and safety measures intense for what's known as a biosafety level 3 lab (BSL-3), the third-highest level of bio-containment precautions (research on the lethal Ebola virus, for instance, requires a BSL-4).

A thumbprint scanner controlled access to the lab's main door. Workers had to change into a one-piece suit with a respirator before working with anthrax spores, and take showers at the end of every shift. A ventilation system filtered any toxins before the air was exhausted outside.

"That's an excellent facility," Heine said. "In fact, when the Centers for Disease Control inspected it, they were impressed. It's a shame it's sitting there idle."

The empty lab is spread over 7,500 square feet on the third floor of the five-story Center for Medical Science across from Albany Medical Center.

It's one of only a handful of BSL-3 labs in the area — the others are operated by the state Health Department and Albany Medical Center — and apparently the single-largest of its kind locally.

Heine and about 20 co-workers were among employees who lost their jobs when the Ordway Reseach Institute Inc. filed for bankruptcy in 2011 and closed.

Ordway, a non-profit biomedical research organization, at one point was the largest tenant in the the 143,000-square-foot building at 150 New Scotland Ave. The firm had wracked up debt and stopped paying its rent.

"It's a very ugly story," Heine said.

He's now a professor at the University of Florida and program director in the College of Medicine's Institute for Therapeutic Innovation. The school has a BSL-3 lab built for infectious disease research, based on Heine's design.

Since Ordway's departure from the Center for Medical Science, the bondholders who financed construction of the $56 million building in 2002 have been trying to sell the building and/or find tenants to fill the empty space, including the BSL-3 lab.

Last year, two separate purchase offers were made, including one from a company that would have filled the remainder of the building with its own employees, said Peter Struzzi, executive managing director at Pyramid Brokerage Co., which represents Wells Fargo Bank N.A., trustee for the bondholders.

In order to complete the deal, Wells Fargo had to buy the Center for Medical Science's long-term ground lease from Renaissance Albany Corp., a non-profit founded by the late philanthropist Morris "Marty" Silverman.

Egan, in an interview, said he's not holding out for more student housing to add to the apartments that Renaissance Albany Corp. leases to 540 students attending nearby colleges, including Albany Law School and Albany College of Pharmacy and Health Sciences.

"That particular building would be a shame to put into housing," Egan said.

He said the prospective buyers of the Center for Medical Science didn't offer enough money for the property.

In recent months, the bondholders were able to sign leases with two new tenants: Island Care Pharmacy of Long Island, which is filling about 3,600 square feet, and National Toxicology Center, which is taking 900 square feet. A letter of intent with a third tenant has been signed, Struzzi said.

"The rental rate has been dramatically reduced to reflect the market," Struzzi said. "From approximately $55 per square foot to $30 per square foot."

An entity affiliated with the state Health Department leases about 63,000 square feet.

It remains to be seen how long it will take to find a user for the BSL-3 lab.

Heine said part of the problem is insufficient federal government funding these days for anthrax-related research because other public health concerns, such as the Zika virus, are bigger priorities.